1. Field of the Invention
The present invention relates to a transmitter-receiver with a built-in regulator used for a mobile terminal.
2. Description of the Related Arts
FIG. 7 is a block diagram illustrating how a GSM (Global System for Mobile communications)-capable mobile terminal is in general configured (for example, refer to FIG. 5 in PCT Patent Laid-open No. WO01/052427). This mobile terminal includes: a base band (hereinafter referred to as “BB”) 102; a transmitter-receiver RF-IC (hereinafter referred to as “RF-IC”); a power amplifier (hereinafter, refer to as PA) 103; an SAW filter (hereinafter refer to as SAW) 104e; and an antenna switch (hereinafter referred to as “ASW”) 105. The BB 102 subjects audio and data to proper signal processing such as encoding, error correction, or modulation and demodulation. The RF-IC subjects an IQ signal coming from the BB 102 to proper processing such as frequency conversion or amplification before outputs the signal to the PA 103. In addition, the RF-IC receives as an input signal an output signal of the SAW 104e to subjects the input signal proper processing such as frequency conversion or amplification before outputs an IQ signal to the BB 102. The PA 103 adds a proper gain to an output signal of the RF-IC. The SAW 104e suppresses unnecessary signals. The ASW 105 is used to properly connect the antenna 111 to the SAW 104e or the PA 103. Since GSM applies the time-division multiplexing (TDMA) method, the antenna 111 is connected to an output end of the PA 103 at the time of transmission, whereas the antenna 111 is connected to an input end of the SAW 104 at the time of receiving. A voltage Vbat is applied to the power supply of the PA 103. Usually, the voltage Vbat is directly supplied from a battery of the mobile terminal. Reference numeral 113d denotes a voltage stabilization regulator (hereinafter referred to as “regulator”). The regulator receives the voltage Vbat as an input voltage, and outputs a voltage that is suitable for the RF-IC 101. For example, the regulator converts a value of the voltage Vbat from 5 V to 2.8 V before outputting the voltage Vbat. An output voltage of the regulator 113d is supplied through wiring 502 to circuit blocks 500a, 500b inside the RF-IC 101. The wiring 502 includes wiring on a mobile terminal substrate, and wiring inside IC. As shown in the figure, power supply wiring of the circuit block 500a and that of the circuit block 500b are separately led out from the RF-IC 101 to the outside so that the length of the wiring inside IC becomes as short as possible.
In recent years, mobile terminals require not only basic functions as a telephone but also additional functions including data communications, a camera function, and a bluetooth function. For this reason, further miniaturization is required for each part constituting a mobile terminal. The RF-IC has been improved in integration degree in order to satisfy the requirement of miniaturization.